All kids are different to what they want to eat.
My youngest has every day a vegemite sandwich (seeded gf bread), some fruit, a boiled egg or a vegetarian sausage, diary free yoghurt, sweet potato/lentil/pea chips or papadums, roast chick peas or roast fava beans, tumeric banana chips (unsweetened). And I bake 1 or 2 times a week wholemeal banana pancakes or zucchini pancakes what goes in the lunch box

Kids at that age are pretty happy with a simple sandwich or wrap. Something like a zucchini slice might be a good variation.

wow that’s strict! mine takes polony and cheese sandwiches most days! boring

Salad wraps, sandwiches, dips with bics and veggie sticks, fruit, yoghurt, dinner left overs

Our preschool has a similar policy.
Generally, ds gets a whole piece of fruit for morning team. Lunch is a sandwich and a piece of fruit or some vegetable sticks.
Things like vegemite, tuna and corn, avocado, ham and tomato are his sandwiches. I also pop in things like cherry tomatoes, carrot, cucumber or fruit.

a lot of daycares and schools, have fridges these days. also if you have a working spare fridge that you don’t want, think about donating it to your local school. it will be appreciated very much and enables the children to have a wider range of food and it is great for summer. yeah try a lot of fruit, crackers, cheese, olives etc. chicken salad, salad sandwiches, popcorn, boiled eggs, egg sandwiches etc

try fruit skewers- it’s a little novelty that might work or a vegie skewer/kebab

Roasted chickpeas. Coconut chips.

ok as a assistant worker in a kindergarten the teachers hate when parents pack
lcm, chips doretos ( corn Chips) lollliy even fruit sticks full of suger.
choc mouse ect

why not do veggie sticks/ fingers, cabana and cheese and crackers saladas and cheese sticks yogurt even fruit salad and a salad lunch, sultanas ct there is so much out there for lunches you will be surprised as long as you have a cold/frozen pack in lunch box every thing will stay cold.
good luck.